#!/bin/sh
#
# Copyright (c) 2007 - 2020 by mod_tile contributors (see AUTHORS file)
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; If not, see http://www.gnu.org/licenses/.

set -e

#------------------------------------------------------------------------------
# AJT - change directory to mod_tile directory so that we can run replag
# and other things directly from this script when run from cron.
# Change the actual location to wherever installed locally.
#------------------------------------------------------------------------------
export PATH=.:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
ACCOUNT=renderaccount
cd /home/$ACCOUNT/src/mod_tile/

#------------------------------------------------------------------------------
# Extra OSM2PGSQL_OPTIONS may need setting if a tag transform script is
# in use.  See https://github.com/SomeoneElseOSM/SomeoneElse-style and
# http://wiki.openstreetmap.org/wiki/User:SomeoneElse/Ubuntu_1404_tileserver_load
# The database name always needs setting.
#------------------------------------------------------------------------------
OSMOSIS_BIN=osmosis
OSM2PGSQL_BIN=osm2pgsql
TRIM_BIN=/home/$ACCOUNT/src/regional/trim_osc.py

DBNAME=gis
OSM2PGSQL_OPTIONS="-d $DBNAME"
#------------------------------------------------------------------------------
# When using trim_osc.py we can define either a bounding box (such as this
# example for England and Wales) or a polygon.
# See https://github.com/zverik/regional .
# This area will usually correspond to the data originally loaded.
#------------------------------------------------------------------------------
TRIM_OPTIONS="-d $DBNAME"
TRIM_REGION_OPTIONS="-b -14.17 48.85 2.12 61.27"
#TRIM_REGION_OPTIONS="-p region.poly"

BASE_DIR=/var/lib/mod_tile
LOG_DIR=/var/log/tiles/
WORKOSM_DIR=$BASE_DIR/.osmosis

LOCK_FILE=/tmp/openstreetmap-update-expire-lock.txt
CHANGE_FILE=$BASE_DIR/changes.osc.gz
EXPIRY_FILE=$BASE_DIR/dirty_tiles
STOP_FILE=$BASE_DIR/stop.txt

OSMOSISLOG=$LOG_DIR/osmosis.log
PGSQLLOG=$LOG_DIR/osm2pgsql.log
EXPIRYLOG=$LOG_DIR/expiry.log
RUNLOG=$LOG_DIR/run.log

#------------------------------------------------------------------------------
# The tile expiry section below can re-render, delete or dirty expired tiles.
# By default, tiles between EXPIRY_MINZOOM and EXPIRY_MAXZOOM are rerendered.
# "render_expired" can optionally delete (and/or dirty) tiles above a certail
# threshold rather than rendering them.
# Here we rerender tiles between zoom levels 13 and 18 and delete between 19
# and 20.
#------------------------------------------------------------------------------
EXPIRY_MINZOOM=13
EXPIRY_TOUCHFROM=21
EXPIRY_DELETEFROM=19
EXPIRY_MAXZOOM=20

#*************************************************************************
#*************************************************************************

m_info() {
  echo "[$(date +"%Y-%m-%d %H:%M:%S")] $$ $1" >>"$RUNLOG"
}

m_error() {
  echo "[$(date +"%Y-%m-%d %H:%M:%S")] $$ [error] $1" >>"$RUNLOG"

  m_info "resetting state"
  /bin/cp $WORKOSM_DIR/last.state.txt $WORKOSM_DIR/state.txt || true

  rm "$CHANGE_FILE" || true
  rm "$EXPIRY_FILE.$$" || true
  rm "$LOCK_FILE"
  exit
}

m_ok() {
  echo "[$(date +"%Y-%m-%d %H:%M:%S")] $$ $1" >>"$RUNLOG"
}

getlock() {
  if [ -s $1 ]; then
    if [ "$(ps -p $(cat $1) | wc -l)" -gt 1 ]; then
      return 1 #false
    fi
  fi

  echo $$ >"$1"
  return 0 #true
}

freelock() {
  rm "$1"
  rm "$CHANGE_FILE"
}

if [ $# -eq 1 ]; then
  m_info "Initialising Osmosis replication system to $1"
  mkdir $WORKOSM_DIR
  $OSMOSIS_BIN --read-replication-interval-init workingDirectory=$WORKOSM_DIR 1>&2 2>"$OSMOSISLOG"
  wget "http://replicate-sequences.osm.mazdermind.de/?"$1"T00:00:00Z" -O $WORKOSM_DIR/state.txt
  mv $WORKOSM_DIR/configuration.txt $WORKOSM_DIR/configuration_orig.txt
  sed "s!baseUrl=http://planet.openstreetmap.org/replication/minute!baseUrl=https://planet.openstreetmap.org/replication/minute!" $WORKOSM_DIR/configuration_orig.txt >$WORKOSM_DIR/configuration.txt
else
  # make sure the lockfile is removed when we exit and then claim it

  if ! getlock "$LOCK_FILE"; then
    m_info "pid $(cat $LOCK_FILE) still running"
    exit 3
  fi

  if [ -e $STOP_FILE ]; then
    m_info "stopped"
    exit 2
  fi

  # -----------------------------------------------------------------------------
  # Add disk space check from https://github.com/zverik/regional
  # -----------------------------------------------------------------------------
  MIN_DISK_SPACE_MB=500

  if $(python -c "import os, sys; st=os.statvfs('$BASE_DIR'); sys.exit(1 if st.f_bavail*st.f_frsize/1024/1024 > $MIN_DISK_SPACE_MB else 0)"); then
    m_info "there is less than $MIN_DISK_SPACE_MB MB left"
    exit 4
  fi

  seq=$(cat $WORKOSM_DIR/state.txt | grep sequenceNumber | cut -d= -f2)

  m_ok "start import from seq-nr $seq, replag is $(osmosis-db_replag -h)"

  /bin/cp $WORKOSM_DIR/state.txt $WORKOSM_DIR/last.state.txt
  m_ok "downloading diff"

  if ! $OSMOSIS_BIN --read-replication-interval workingDirectory=$WORKOSM_DIR --simplify-change --write-xml-change $CHANGE_FILE 1>&2 2>"$OSMOSISLOG"; then
    m_error "Osmosis error"
  fi

  m_ok "filtering diff"
  if ! $TRIM_BIN $TRIM_OPTIONS $TRIM_REGION_OPTIONS -z $CHANGE_FILE $CHANGE_FILE 1>&2 2>>"$RUNLOG"; then
    m_error "Trim_osc error"
  fi

  m_ok "importing diff"
  #------------------------------------------------------------------------------
  # Previously openstreetmap-tiles-update-expire tried to dirty layer
  # "$EXPIRY_MAXZOOM - 3" (which was 15) only.  Instead we write all expired
  # tiles in range to the list (note the "-" rather than ":" in the "-e"
  # parameter).
  #------------------------------------------------------------------------------
  if ! $OSM2PGSQL_BIN -a --slim -e$EXPIRY_MINZOOM-$EXPIRY_MAXZOOM $OSM2PGSQL_OPTIONS -o "$EXPIRY_FILE.$$" $CHANGE_FILE 1>&2 2>"$PGSQLLOG"; then
    m_error "osm2pgsql error"
  fi

  #------------------------------------------------------------------------------
  # The lockfile is normally removed before we expire tiles because that is
  # something thatcan be done in parallel with further processing.  In order to
  # avoid rework, if actually rerendering is done rather than just deleting or
  # dirtying, it makes sense to move it lower down.
  #------------------------------------------------------------------------------
  #    m_ok "Import complete; removing lock file"
  #    freelock "$LOCK_FILE"

  m_ok "expiring tiles"
  #------------------------------------------------------------------------------
  # When expiring tiles we need to define the style sheet if it's not "default".
  # In this case it's "ajt".
  # Previously all tiles on the "dirty" list between $EXPIRY_MINZOOM and
  # $EXPIRY_MAXZOOM were dirtied.  We currently re-render
  # tiles >= $EXPIRY_MINZOOM and < $EXPIRY_DELETEFROM, expiry from 14 and
  # delete >= $EXPIRY_DELETEFROM and <= $EXPIRY_MAXZOOM.
  # The default path to renderd.sock is fixed.
  #
  # Note no --touch-from=$EXPIRY_TOUCHFROM
  #------------------------------------------------------------------------------
  if ! render_expired --map=ajt --min-zoom=$EXPIRY_MINZOOM --delete-from=$EXPIRY_DELETEFROM --max-zoom=$EXPIRY_MAXZOOM -s /var/run/renderd/renderd.sock <"$EXPIRY_FILE.$$" 2>&1 | tail -8 >>"$EXPIRYLOG"; then
    m_info "Expiry failed"
  fi

  rm "$EXPIRY_FILE.$$"

  #------------------------------------------------------------------------------
  # Only remove the lock file after expiry (if system is slow we want to delay
  # the next import, not have multiple render_expired processes running)
  #------------------------------------------------------------------------------
  freelock "$LOCK_FILE"

  m_ok "Done with import"

fi
